Being able to Drag Zoom makes it easy to view a specific region of your sequence in greater detail. To Drag Zoom, just hold down the mouse button and drag the cursor along your sequence. The Map view will redraw to show the selected area in greater detail.
Once you are zoomed in you have a few options to choose the region, or to zoom back out.
The cursor keys also work:
As well as using Drag Zoom you can also zoom magnify the entire sequence. Use the magnification cursor in the Graphics Palette to do that. Then hold down the OPTION key to reverse that when you click.
